13B-12V10 MR-372-J84-13B100$040.mif
13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
System outline
The DCM1.2 injection system used on the K9K engine is an electronically-managed high pressure injection system.
The fuel is compressed by a high pressure pump then stored in a rail that feeds the injectors. Injection takes place
when a current pulse is applied to the injector holders. The amount injected is proportional to the rail pressure
and the applied pulse length, and the start of injection is synchronised with the start of the pulse.
The system includes two subsystems, which have different fuel pressure levels:
–The low pressure circuit contains the tank, the diesel fuel filter, the transfer pump and the injector holder
return pipes,
–the high-pressure system includes the high-pressure pump, rail, injector holders and high-pressure pipes.
Finally, there are a certain number of sensors and regulating actuators for controlling and monitoring the entire
system.
Functions performed:
Function: Fuel supply management (timing, flow and pressure).
Quantity of fuel injected and injection timing setting
The injection checking parameters are the quantities to be injected and their respective timing.
These are calculated by the computer using signals from the following sensors:
–engine speed sensor (Crankshaft + Cam lobe for synchronisation),
–accelerator pedal sensor,
–coolant temperature sensor,
–rail pressure sensor,
–atmospheric pressure sensor,
–accelerometer,
–inlet manifold pressure sensor.
Specific vehicle / engine suffix details:
Modus
K9K 750 752 (Euro 3)Inlet manifold temperature and pressure sensor (a sensor which has two functions),
management by the turbocharger control solenoid valve inlet pressure.
K9K 766 (Euro 4)Either a flow sensor with an integrated temperature sensor or a temperature sensor
instead of a flow sensor with inlet manifold temperature sensor, inlet manifold pressure
sensor, management by turbocharger control solenoid valve programming.
K9K 768 (Euro 4)Flow sensor with integrated temperature sensor, inlet manifold pressure sensor,
management by the turbocharger control solenoid valve inlet pressure.
DIESEL INJECTION
Fault finding – Function
